Apparatus for the production of nitrogen compounds.



cA KRAIISS (I, P. SIHELIN. APPARATUS FOR THE PRODUCTION GF NITROGEN CUMPGUNDS.

APPLICATION FILED MAH. 26,1915.

APPARATUS FOR THE PRODUCTION OF NITROGEN COMPOUNDS.

APPLlc/Tlon FILED MAR.26,1915.

1 ,21 1,181 Patented Jan. 2, 1917 2 SHEETS-SHEEY 2.

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CONSTANTIN KRAUSS, OF COLOGNE-BRAUNSFELD, AND PAUL STHELIN, OF KNAP-4 SACK, NEAR COLOGNE, GERMANY.

APPARATUS FOR THE PRODUCTION 0F NITROGEN COMPOUNDS.

Specification of Letters Patent.

Patented J an. 2, 1917.

Original application led December 6, 1913, Serial No. 85,180. Divided and this application tiled March 26, 1915. Serial No. 17,286.

To all whom it may concern.'

Be it known that We, CONSTANTIN KRAUss and PAUL STHELIN, subjects of the King of Prussia, ierman Emperor, residing at (l) Cologne-Braunsfeld and (Q) Knapsack, near Cologne, Germany, have invented certain new and useful Improvements in Apparatus for the Production `of Nitrogen Compounds, of which the following is a specification, reference being had therein to the accompanying drawing.

This invention relates to an apparatus for the production of nitrogen compounds, more esliecially for the execution of the process described in our application No. 805180, tiled Der.. (i, 1913, the present application being a divisional application thereof. The said process consists essentially in passing the metal carbid through a preheatmg space, a heating space, and a reduction space and then passing the metal carbid through a cooling space.

The accompanying drawing shows a simple apparatus for carrying out this process, in which Figure l shows a longitudinal section of a channel furnace. Fig. 2 shows a modication of the apparatus shown in Fig. 1, and Fig. 3 is a plan View on the line mof Fig. 2.

For the first mode of Working described in our Specification 805180, there is employed a horizontal channel furnace (Fig. l). -This furnace consists of four parts: 1, a preliminary heating space; 2, a full heating space; 3, a reaction space, and 4, a cooling space.

In the preliminary heating Zone or space V the reaction product (finely pulverized carbid or carbid mixtureswith or Without additions which facilitate the reaction) is warmed by means of the gases escaping from the other spaces. In the heating zone H, the carbid is heated up to the temperature necessary for the carrying out of the reaction. In the reaction zone or space R the treatment with nitrogen is effected; in the cooling space K, the finished product is cooled down until it can be Withdrawn Without special precautions and can be further utilized.

The method of working is as follows The finely pulverized material, to which substances facilitating the reaction can be added, is transported by mechanical means, such as tracks, transporting bands or the like through the furnaces. In the contrary direction to that in which the material to be treated with nitrogen is transported, there is admitted cold nitrogen gas. In the preliminary heating space the escaping gases give up part of their heat to the material and are drawn'oif comparatively cool. The material then passes somewhat warmed into the heating space, where it is heated up to the reaction temperature, either by means of an electric heating device or by outside fire. The consumption of heat energy is thus very small, because the nitrogen gas coming from the cooling and reaction spaces is already so hot, that it reacts upon the material to be nitrogenized causing further reaction heat to be liberated which again supports the reaction. The heating space serves therefore properly only as a heat regulator.

From the heating space, the reaction mass passes into the reaction space. There is here a space between the cool inflowing nitrogen gas and the reaction masses proceeding out of the heating space of such a kind that under all circumstances, the 'reaction mass before cooling must exceed the critical` temperature which assures the quantitative nitrogenizing and prevents any reformation of the carbid. As above stated. it is necessary to Work with a quite extraordinarily great surplus of cold nitrogen in order to overcome by this means the degrees of heat liberated. This would, however, render the process very costly and moreover enable no certain working reaction because under certain circumstances, during short interruptions of the operation, local 'heating can take place which might injure the material in the furnace or the transporting mechanism. We have therefore in addition to the regulatable intermal supply of the cool nitrogen current, also devised a regulation of the furnace by outward cooling. For this purpose, We have surrounded the channel furnace with an outer cooling mantle and have c'onstrueted the inner `mantle from material which conducts heat. By this arrangement it becomes possible whenever the various A ranged to allow measuring instruments inserted in the reaction space indicate an undesirable rise of temperature, to act immediately upon the temperature by passing Cold air between the Channel furnace and theV mantle. lu this manner therefore, a double temperature regulation takes plare, firstly hy the nitrogen in the interior ot the channel furnace and secondly hy air and cooling gases at the outside. Ae the overheating (as already Stated) is rhielly local, We have arthe fold nitrogen gas to How into the rom-tion spare :it Vai-ione points to regulate tvu'ulwratures. idoreorer, we have divided the rooling spare between the rhannei fui-nare and the outer mantle in various .lirisioue. as may be .eeuu iu the drawing, whereby we art` in the position to rool certain parte ot' the rhannel tui-name arro'rdiner to rerulireinent.

From the rear-tion sparo the rem-ting' inatorial pausen into the rooling spare aud is also Capable of being roolt'd down by eurronluling' air So that the reaf'tiou mafie can be so far ooled that its removal from the turnate and its, 'further treatment is; not hindered.

For the eeroud niethod of working described in our application $05180 in ufhirh the material absorbing the` nitrogen is not moved but remainr; at the saine position in the furnam: until it is ifompletely" used up. a kind of rin;r `t'urnaee (Figs. and Ill is proridml, the operation of whirh ie as l'ollou Si In the rarioue Chaudiere or non@4 ot' the turnace (Figa. L and I5) the carbid or the earbid mixture ia apread out on otages in iayere. The` separate Chaudiere Il. l?. are prorided with suitable` heating deviner; ii Vfor electric internal lli-ating. The nitrogen enters, at rai-huis pointe in the separato rhauibere, For the 'onuururcauent ot the prot-rss" tl'url is tiret heated one rhainber or zone t0 the` reaction temperature, then cooled nitrogen ie passel in and in suoli a tulautityY that the :aune suliirt` to prevent the rvartiou trulpt-laturr rieing); hovond the best point. For this tlurtl are` obviously `required inurl, gri-rater duantitiife, of gar; than are needed for the lSaturation ol' the rarbid whirh is in thi.` vhuuiber. 'i'lunniouf-rulned hlghl)v heated nitrogen is introdzu-vd in thtl arr-ond hainber and realts upon ilu' rarbidet there. lil/uro again. reaction heat in lboratrd wliirh ri'ouid had to the overheating of they reavtion prodiu't. [u order to prevent this roohrd nitro- ;Ivn is iutrodurrd in suoli quantities that the over ruaftiou temperature ie not uXrtrdi-d. 'The nitrogen ire paf-evd through thvy tirs-t r'hanlbvr until they maSS IH Sutiiuitntlr mailed. This hot nitrogen passers an already staterh l'roni thtl tiret into the Sur-,ond rhaiuber. "ghe truuarature of the nitrogen pasfaiug in is lowered but iu thtdegree that the rtartiou produf-t in added in the rharnbur. vor

fluently the introduction of Afresh Cold nitrogen in the second chamber nlnet be gradually reduced.

The saine operation takes place in the third f hainber again and so forth. The heating` of the rhainhers will therefore only need to he undertaken when tor some reason, a` rhamuer has; not attained to the necessary reaction tempelntore or when a furnace being; newly started. AS even in this Inode of workin". local orerheatings are not irnnoaeibh. we have ronetrurted in the Separate reaction rhauihers tooling tubes or cooling; hone-1 i of material uhirh easily {rondurte heat.` 'through uhith cold air can be paez al. a5 noon as thel measuring instrlnneuts indicatean uudeeirable risey of temperature.

lt uill be ohrioim4 without further explanation that tirotliT a rhoking ot' such apparatuc-ve is i'ei'idered impossihle, whereby a unitorui action ot the nitrogen Seemed, and that etwondly. au injurituis overheating of the rem-tion produit and a decomposition of. the nitrogen Compound already formed is; rendered ilupoaeibleH because in the attaining' ot thi moe-t Suitable reartiou temperature. no owrluating;l hut rather a gradual tooling' takes place in the nitrogen current, and bet-aime moremer the reaction produet learns the apparatusV rooled. ,ilrfcording to our prowess there arises in the action of nitrogen ou rai-bid a mixture of nitrogen roinpoundi-l. .'l it-tly ralviuui ryanamid, and :den dir rzmdiunlid and ryanainid. 3y proper additions we are in a position to inert-age the produrtion ot one ot' the latter produe-tsI at the` expr-uen of the ryanarnid. Fiuaily' the aaring; of heat ie the most Favorablt` [mesihh berauuu both the heat which is in the prodnrt lett in the furnace is ahaorbvd by the iur-,outing rurrent ol r'old nitrogen grae and also the heat oi' the nitrogen gas whit-h drawn of is tontinuousdrvv trans- Vlim-rrd to the newly rharged rtat'tion masa, and aleo the reartion heat liberated during the rrnrtiou is so controlled that it coperater: to ac-zsif-t and not to injure the process. Saving: ot heat avrording to our proreSS is arlualti' So Vfavorable that the reaction prorrf-de ah'uoat entirely without the addition ot' lu-at troni without when once the mass in the 'Turn-awe haz-i been hronght to the requieit s trainer-Mure'. The heating7 devices then serre simply as regulators of the temperature.

Haring now nartirularly descril'ied and aerrrtaiuvd thel nature of our said invention and in what manner the saine is to be. periornuth we dur-.lare that what we claim ist#- l. Nn amiaratus t'or the continuous produrtion ol^ nitrogen rompounds: from nletai farhide and nitrogen. comprising an elongated tornava nir-ans for tranporting the wird wal-hide through mid 'furnace in one dira-"tion, oleane l'or introducing nitrogen Vmetal carbids tl1rough said furnace 1n one direction, means for introducing p nitrogen through said furnace 1n a d1rect1on opposed v to the `travel of said transporting means,

means for regulating the supply of said nitrogen, and means for cooling the major portion of said furnace. y i

3. An apparatus for the continuous production of nitrogen compounds from metal lcarbids and nitrogen, comprising an elongatf-d furnace, means for transporting the metal carbide-through said furnace in one direction, means for introducing nitrogen through said furnace in a direction opposed to the travel of said transporting means, independent means for successively regulating the supply of said nitrogen, and means for cooling the major portion of said furnace.

4. A n a paratus for the continuous production ot nitrogen compounds from metal carbids and nitrogen, comprising afurnace arranged to provide a plurality of zones,

means for transporting the 'metal carbide' progressively through said zones in one direct-ion, means for introducing nitrogen through said zones in a direction opposed to the travel of said transportin means, means for regulating the supply o said nitrogen, and means-'for cooling the major portion of said furnace.

5. An a. paratus for the continuous production o nitrogen compounds from metal eax-bids and nitrogen, comprising a furnace l arranged to provide a prelieatmg zone, ay

main heatingzone, a reaction zone and a.

cooling zone, means for transporting `the metal carbide progressively through said zones, mea-ns`- for introduci'n to the travel of said transporting ineens, means for regulating the supply n said ni trugen, and menus for coo ing the :major :-y

portion of said furnace.

G. An apparatus for the cmil'inuous production of nitrogen compounds from metal carbids and nitrogen, comprising a furnace arranged to provide an inner section and an outer section, said furnace having a preheating zone, a main heating zone, av reaction zone and a cooling zone, means for transporting the metal carbids throu h said in ner section in one direction, means gol' introducing nitrogen through said inner section in a direction opposed to that of the travel of said transporting means, and means opening through said outer section for introduca a cooling medium to the major Portion o said inner section.

7. An apparatus for the continuous production of nitrogen compounds from metal carbids and nitrogen, comprising a furnace arranged to provide an inner section and an outer section, said furnace having a preheating zone, a. main heating zone, a reaction zone and a cooling zone, means for transporting the metal carbids through said inner section in one direction, means for introducing nitro n through said innersection in a direction opposed to the travel of said-` transporting means, means for regulating thesupply of said nitroen, a plurality of cooling chambers forme interiori of said outer section and surrounding sai inner section, and means for introducing a cooling medium to said chambers.

In testimony whereof we afiix our signatures in the resence of two witnesses.

ONSTANHN KRAUSS.

. PAUL STAHELIN.

Witnesses:

J. Wuming, It. Deer-1N.:

l nitrogen 4 through said zones in n 'direction opposed 

